Image projection systems may be used to enlarge a still or video image, or to enable the image to be viewed simultaneously by a large or small audience. As both projection devices and the personal computers used to drive them have become increasingly smaller and more portable, it has become possible to give sophisticated visual presentations in venues that were previously inaccessible.
Unfortunately, although modern projection equipment may now require only a power socket, many rooms may lack a suitable projection surface. Bringing along a projection screen, however, may compromise the portability of modern projection apparatus. The alternative, projection of an image onto even a lightly colored wall, may detract from the content of the presentation. A projection system that actively compensates for the color characteristics of a projection surface thus would be desirable.